Shouldn't Raven be Apple's step-aunt?

I kind a of always had a similar to how marriages work in EAH. I mean if they have to follow their parents the exact way it happened including marrying the sons oder daughters of the other side of their family;Isn't that incest? Aren't apfel, apple and charming twins oder something? This kind of thing has been bugging me for quite awhile even though it's just a nitpick.Especially since Daring and apfel, apple do in fact look a little too similar for my liking.

ya um raven Queen is actually apfel, apple whites aunt because if u think back ravens dad is snow whites dad so she is snow whites half sister which makes her apples aunt

This had me really confused, but the truth of the matter is we don’t know how many generations apfel, apple white is to the original snow white, so we don’t exactly know how close relation apfel, apple and raven are per say. I did Google it and it sagte they had gone down so many generations so it’s hard to say they are exactly related, but again i’m really not too sure.